Binary compounds of zinc are known for most of the metalloids and all the nonmetals except the noble gases. The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric, dissolving in both strong basic and acidic solutions. The other chalcogenides (ZnS, ZnSe, and ZnTe) have varied applications in electronics and optics. Pnictogenides (Zn
3N
2, Zn
3P
2, Zn
3As
2 and Zn
3Sb
2), the peroxide (ZnO
2), the hydride (ZnH
2), and the carbide (ZnC
2) are also known. Of the four halides, ZnF
2 has the most ionic character, whereas the others (ZnCl
2, ZnBr
2, and ZnI
2) have relatively low melting points and are considered to have more covalent character.
What applications do chalcogenides have?
electronics and optics.

Many assembled PCBs are static sensitive, and therefore must be placed in antistatic bags during transport. When handling these boards, the user must be grounded (earthed). Improper handling techniques might transmit an accumulated static charge through the board, damaging or destroying components. Even bare boards are sometimes static sensitive. Traces have become so fine that it's quite possible to blow an etch off the board (or change its characteristics) with a static charge. This is especially true on non-traditional PCBs such as MCMs and microwave PCBs.
Non-traditional PCBs include microwave PCBs and what other type of board?
MCMs

The second and most dramatic boom and bust resulted from the Klondike Gold Rush, which ended the depression that had begun with the Panic of 1893; in a short time, Seattle became a major transportation center. On July 14, 1897, the S.S. Portland docked with its famed "ton of gold", and Seattle became the main transport and supply point for the miners in Alaska and the Yukon. Few of those working men found lasting wealth, however; it was Seattle's business of clothing the miners and feeding them salmon that panned out in the long run. Along with Seattle, other cities like Everett, Tacoma, Port Townsend, Bremerton, and Olympia, all in the Puget Sound region, became competitors for exchange, rather than mother lodes for extraction, of precious metals. The boom lasted well into the early part of the 20th century and funded many new Seattle companies and products. In 1907, 19-year-old James E. Casey borrowed $100 from a friend and founded the American Messenger Company (later UPS). Other Seattle companies founded during this period include Nordstrom and Eddie Bauer. Seattle brought in the Olmsted Brothers landscape architecture firm to design a system of parks and boulevards.
After lumbering, what was Seattle's second big economic boom?

Klondike Gold Rush